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The Working Party on Safety in Biotechnology of the European Federation of Biotechnology has proposed a classification of microorganisms that cause diseases in plants. In this paper appropriate safety levels are proposed for these classes of microorganisms in order to ensure that research, development and industrial fermentation work with plant pathogens will limit the risk of outbreaks of diseases in crops that could result from work with such microorganisms when they are cultivated in laboratories, glasshouses and biotechnology installations.Co-opted: J. Dähne, J. Drozd, M. Lemattre, I. M. Smith , E. M. A. WaterschootA Report prepared by the Working Party on Safety in Biotechnology of the European Federation of Biotechnology (EFB)
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Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication.  相似文献   
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Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication.  相似文献   
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We previously described an enrichment-immunoassay utilizing a T6 monoclonal antibody capture enzyme-linked immunosorbent assay. Here we evaluated it for the rapid screening for Salmonella in fishmeal obtained from the national Animal and Plant Quarantine service in the People's Republic of China. In this method, the number of Salmonella present is first expanded by appropriate enrichment cultures, and the pathogens are then directly detected by the T6 immunoassay. In a total of 94 enrichment cultures of fishmeal, we obtained an overall concordance of 98% between the results obtained in parallel by this method and by conventional test method. The positive prediction by this method was 92% and the negative prediction was 100%. The turn around time for the new test was 27 h which is a significant improvement from the turn around time exceeding 96 h required for the conventional test method. This test proved to be compatible with the routine work flow in the practical setting of a quarantine laboratory.  相似文献   
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Risk assessment for the deliberate release of microorganisms into the environment is traditionally carried out on a case-by-case basis. In a similar approach to that used when assessing human pathogenicity, we propose an alternative approach by introducing risk classes to facilitate or complement this type of risk assessment. These consider several sets of scenarios that address the different values that need to be protected. Examples of this approach include risk-class definitions for soil fertility and biodiversity.  相似文献   
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Background  

Mannose binding lectin (MBL) is an important host defence protein against opportunistic fungal pathogens. This carbohydrate-binding protein, an opsonin and lectin pathway activator, binds through multiple lectin domains to the repeating sugar arrays displayed on the surface of a wide range of clinically relevant microbial species. We investigated the contribution of MBL to antifungal innate immunity towards C. parapsilosis in vitro.  相似文献   
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Brain structural alterations and neuropsychiatric symptoms have been described repeatedly in Fabry disease, yet cognitive deficits have been shown to be only mild. Here, we aimed to investigate neuropsychiatric symptoms and brain structure longitudinally. We expected no clinically relevant increase of neuropsychiatric symptoms in parallel to increased brain structural alterations. We assessed 14 Fabry patients (46.1 ± 10.8 years) who had participated in our investigation eight years ago. Patients engaged in neuropsychiatric testing, as well as structural magnetic resonance imaging and angiography to determine white matter lesions, hippocampal volume, and the diameter of the larger intracranial arteries. While Fabry patients did not differ on cognitive performance, they showed progressive and significant hippocampal volume loss over the 8-year observation period. White matter lesions were associated with older age and higher white matter lesion load at baseline, but did not reach statistical significance when comparing baseline to follow-up. Likewise, intracranial artery diameters did not increase significantly. None of the imaging parameters were associated with the neuropsychiatric parameters. Depression frequency reduced from 50% at baseline to 21% at follow-up, but it did not reach significance. This investigation demonstrates clinical stability in cognitive function, while pronounced hippocampal atrophy is apparent throughout the 8 years. Our middle-aged Fabry patients appeared to compensate successfully for progressive hippocampal volume loss. The hippocampal volume decline indicates brain regional neuronal involvement in Fabry disease.  相似文献   
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The idea of immunological surveillance against cancer has existed for nearly 100 years but as no conclusive evidence has yet been published the importance of the cellular immune defense in the detection and removal of incipient or existing tumors is still a hotly debated subject. However, in order to select a relevant immunotherapeutic strategy in the treatment of cancer, a fundamental understanding of the basic immunologic conditions under which a tumor develops and exists is a prerequisite. Therefore, a murine model was set up that we hoped would enable us to confirm or reject the theory of immunological surveillance. A large panel of methylcholanthrene induced tumors was established in T-cell immunodeficient nude mice and congenic normal mice to study the influence of the immune system on developing tumors. As nude mice developed tumors fastest and with the highest incidence, we concluded that in this model the immune system constituted a ‘tumor-suppressive factor’ delaying and sometimes abrogating tumor growth, i.e. performing immune surveillance. Immunogenicity of the tumors was assessed by transplantation back to normal histocompatible mice. Tumors originating from the immunodeficient nude mice turned out to be far more immunogenic than tumors from normal mice, resulting in a high rejection rate. CD8+cytotoxic T cells were found to be indispensable for this rejection, leading to the conclusion that the cytotoxic T cells perform immune selection in normal mice, eliminating immunogenic tumor cell variants in the incipient tumor. In this review, we discuss the difficulties facing immunotherapy when conclusions are drawn from the presented observations and hypotheses.  相似文献   
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